1 /* 2 * Parade PS8622 eDP/LVDS bridge driver 3 * 4 * Copyright (C) 2014 Google, Inc. 5 * 6 * This software is licensed under the terms of the GNU General Public 7 * License version 2, as published by the Free Software Foundation, and 8 * may be copied, distributed, and modified under those terms. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 */ 15 16 #include <linux/backlight.h> 17 #include <linux/delay.h> 18 #include <linux/err.h> 19 #include <linux/gpio.h> 20 #include <linux/gpio/consumer.h> 21 #include <linux/i2c.h> 22 #include <linux/module.h> 23 #include <linux/of.h> 24 #include <linux/of_device.h> 25 #include <linux/of_graph.h> 26 #include <linux/pm.h> 27 #include <linux/regulator/consumer.h> 28 29 #include <drm/drm_panel.h> 30 31 #include "drmP.h" 32 #include "drm_crtc.h" 33 #include "drm_crtc_helper.h" 34 #include "drm_atomic_helper.h" 35 36 /* Brightness scale on the Parade chip */ 37 #define PS8622_MAX_BRIGHTNESS 0xff 38 39 /* Timings taken from the version 1.7 datasheet for the PS8622/PS8625 */ 40 #define PS8622_POWER_RISE_T1_MIN_US 10 41 #define PS8622_POWER_RISE_T1_MAX_US 10000 42 #define PS8622_RST_HIGH_T2_MIN_US 3000 43 #define PS8622_RST_HIGH_T2_MAX_US 30000 44 #define PS8622_PWMO_END_T12_MS 200 45 #define PS8622_POWER_FALL_T16_MAX_US 10000 46 #define PS8622_POWER_OFF_T17_MS 500 47 48 #if ((PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US) > \ 49 (PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US)) 50 #error "T2.min + T1.max must be less than T2.max + T1.min" 51 #endif 52 53 struct ps8622_bridge { 54 struct drm_connector connector; 55 struct i2c_client *client; 56 struct drm_bridge bridge; 57 struct drm_panel *panel; 58 struct regulator *v12; 59 struct backlight_device *bl; 60 61 struct gpio_desc *gpio_slp; 62 struct gpio_desc *gpio_rst; 63 64 u32 max_lane_count; 65 u32 lane_count; 66 67 bool enabled; 68 }; 69 70 static inline struct ps8622_bridge * 71 bridge_to_ps8622(struct drm_bridge *bridge) 72 { 73 return container_of(bridge, struct ps8622_bridge, bridge); 74 } 75 76 static inline struct ps8622_bridge * 77 connector_to_ps8622(struct drm_connector *connector) 78 { 79 return container_of(connector, struct ps8622_bridge, connector); 80 } 81 82 static int ps8622_set(struct i2c_client *client, u8 page, u8 reg, u8 val) 83 { 84 int ret; 85 struct i2c_adapter *adap = client->adapter; 86 struct i2c_msg msg; 87 u8 data[] = {reg, val}; 88 89 msg.addr = client->addr + page; 90 msg.flags = 0; 91 msg.len = sizeof(data); 92 msg.buf = data; 93 94 ret = i2c_transfer(adap, &msg, 1); 95 if (ret != 1) 96 pr_warn("PS8622 I2C write (0x%02x,0x%02x,0x%02x) failed: %d\n", 97 client->addr + page, reg, val, ret); 98 return !(ret == 1); 99 } 100 101 static int ps8622_send_config(struct ps8622_bridge *ps8622) 102 { 103 struct i2c_client *cl = ps8622->client; 104 int err = 0; 105 106 /* HPD low */ 107 err = ps8622_set(cl, 0x02, 0xa1, 0x01); 108 if (err) 109 goto error; 110 111 /* SW setting: [1:0] SW output 1.2V voltage is lower to 96% */ 112 err = ps8622_set(cl, 0x04, 0x14, 0x01); 113 if (err) 114 goto error; 115 116 /* RCO SS setting: [5:4] = b01 0.5%, b10 1%, b11 1.5% */ 117 err = ps8622_set(cl, 0x04, 0xe3, 0x20); 118 if (err) 119 goto error; 120 121 /* [7] RCO SS enable */ 122 err = ps8622_set(cl, 0x04, 0xe2, 0x80); 123 if (err) 124 goto error; 125 126 /* RPHY Setting 127 * [3:2] CDR tune wait cycle before measure for fine tune 128 * b00: 1us b01: 0.5us b10:2us, b11: 4us 129 */ 130 err = ps8622_set(cl, 0x04, 0x8a, 0x0c); 131 if (err) 132 goto error; 133 134 /* [3] RFD always on */ 135 err = ps8622_set(cl, 0x04, 0x89, 0x08); 136 if (err) 137 goto error; 138 139 /* CTN lock in/out: 20000ppm/80000ppm. Lock out 2 times. */ 140 err = ps8622_set(cl, 0x04, 0x71, 0x2d); 141 if (err) 142 goto error; 143 144 /* 2.7G CDR settings: NOF=40LSB for HBR CDR setting */ 145 err = ps8622_set(cl, 0x04, 0x7d, 0x07); 146 if (err) 147 goto error; 148 149 /* [1:0] Fmin=+4bands */ 150 err = ps8622_set(cl, 0x04, 0x7b, 0x00); 151 if (err) 152 goto error; 153 154 /* [7:5] DCO_FTRNG=+-40% */ 155 err = ps8622_set(cl, 0x04, 0x7a, 0xfd); 156 if (err) 157 goto error; 158 159 /* 1.62G CDR settings: [5:2]NOF=64LSB [1:0]DCO scale is 2/5 */ 160 err = ps8622_set(cl, 0x04, 0xc0, 0x12); 161 if (err) 162 goto error; 163 164 /* Gitune=-37% */ 165 err = ps8622_set(cl, 0x04, 0xc1, 0x92); 166 if (err) 167 goto error; 168 169 /* Fbstep=100% */ 170 err = ps8622_set(cl, 0x04, 0xc2, 0x1c); 171 if (err) 172 goto error; 173 174 /* [7] LOS signal disable */ 175 err = ps8622_set(cl, 0x04, 0x32, 0x80); 176 if (err) 177 goto error; 178 179 /* RPIO Setting: [7:4] LVDS driver bias current : 75% (250mV swing) */ 180 err = ps8622_set(cl, 0x04, 0x00, 0xb0); 181 if (err) 182 goto error; 183 184 /* [7:6] Right-bar GPIO output strength is 8mA */ 185 err = ps8622_set(cl, 0x04, 0x15, 0x40); 186 if (err) 187 goto error; 188 189 /* EQ Training State Machine Setting, RCO calibration start */ 190 err = ps8622_set(cl, 0x04, 0x54, 0x10); 191 if (err) 192 goto error; 193 194 /* Logic, needs more than 10 I2C command */ 195 /* [4:0] MAX_LANE_COUNT set to max supported lanes */ 196 err = ps8622_set(cl, 0x01, 0x02, 0x80 | ps8622->max_lane_count); 197 if (err) 198 goto error; 199 200 /* [4:0] LANE_COUNT_SET set to chosen lane count */ 201 err = ps8622_set(cl, 0x01, 0x21, 0x80 | ps8622->lane_count); 202 if (err) 203 goto error; 204 205 err = ps8622_set(cl, 0x00, 0x52, 0x20); 206 if (err) 207 goto error; 208 209 /* HPD CP toggle enable */ 210 err = ps8622_set(cl, 0x00, 0xf1, 0x03); 211 if (err) 212 goto error; 213 214 err = ps8622_set(cl, 0x00, 0x62, 0x41); 215 if (err) 216 goto error; 217 218 /* Counter number, add 1ms counter delay */ 219 err = ps8622_set(cl, 0x00, 0xf6, 0x01); 220 if (err) 221 goto error; 222 223 /* [6]PWM function control by DPCD0040f[7], default is PWM block */ 224 err = ps8622_set(cl, 0x00, 0x77, 0x06); 225 if (err) 226 goto error; 227 228 /* 04h Adjust VTotal toleranceto fix the 30Hz no display issue */ 229 err = ps8622_set(cl, 0x00, 0x4c, 0x04); 230 if (err) 231 goto error; 232 233 /* DPCD00400='h00, Parade OUI ='h001cf8 */ 234 err = ps8622_set(cl, 0x01, 0xc0, 0x00); 235 if (err) 236 goto error; 237 238 /* DPCD00401='h1c */ 239 err = ps8622_set(cl, 0x01, 0xc1, 0x1c); 240 if (err) 241 goto error; 242 243 /* DPCD00402='hf8 */ 244 err = ps8622_set(cl, 0x01, 0xc2, 0xf8); 245 if (err) 246 goto error; 247 248 /* DPCD403~408 = ASCII code, D2SLV5='h4432534c5635 */ 249 err = ps8622_set(cl, 0x01, 0xc3, 0x44); 250 if (err) 251 goto error; 252 253 /* DPCD404 */ 254 err = ps8622_set(cl, 0x01, 0xc4, 0x32); 255 if (err) 256 goto error; 257 258 /* DPCD405 */ 259 err = ps8622_set(cl, 0x01, 0xc5, 0x53); 260 if (err) 261 goto error; 262 263 /* DPCD406 */ 264 err = ps8622_set(cl, 0x01, 0xc6, 0x4c); 265 if (err) 266 goto error; 267 268 /* DPCD407 */ 269 err = ps8622_set(cl, 0x01, 0xc7, 0x56); 270 if (err) 271 goto error; 272 273 /* DPCD408 */ 274 err = ps8622_set(cl, 0x01, 0xc8, 0x35); 275 if (err) 276 goto error; 277 278 /* DPCD40A, Initial Code major revision '01' */ 279 err = ps8622_set(cl, 0x01, 0xca, 0x01); 280 if (err) 281 goto error; 282 283 /* DPCD40B, Initial Code minor revision '05' */ 284 err = ps8622_set(cl, 0x01, 0xcb, 0x05); 285 if (err) 286 goto error; 287 288 289 if (ps8622->bl) { 290 /* DPCD720, internal PWM */ 291 err = ps8622_set(cl, 0x01, 0xa5, 0xa0); 292 if (err) 293 goto error; 294 295 /* FFh for 100% brightness, 0h for 0% brightness */ 296 err = ps8622_set(cl, 0x01, 0xa7, 297 ps8622->bl->props.brightness); 298 if (err) 299 goto error; 300 } else { 301 /* DPCD720, external PWM */ 302 err = ps8622_set(cl, 0x01, 0xa5, 0x80); 303 if (err) 304 goto error; 305 } 306 307 /* Set LVDS output as 6bit-VESA mapping, single LVDS channel */ 308 err = ps8622_set(cl, 0x01, 0xcc, 0x13); 309 if (err) 310 goto error; 311 312 /* Enable SSC set by register */ 313 err = ps8622_set(cl, 0x02, 0xb1, 0x20); 314 if (err) 315 goto error; 316 317 /* Set SSC enabled and +/-1% central spreading */ 318 err = ps8622_set(cl, 0x04, 0x10, 0x16); 319 if (err) 320 goto error; 321 322 /* Logic end */ 323 /* MPU Clock source: LC => RCO */ 324 err = ps8622_set(cl, 0x04, 0x59, 0x60); 325 if (err) 326 goto error; 327 328 /* LC -> RCO */ 329 err = ps8622_set(cl, 0x04, 0x54, 0x14); 330 if (err) 331 goto error; 332 333 /* HPD high */ 334 err = ps8622_set(cl, 0x02, 0xa1, 0x91); 335 336 error: 337 return err ? -EIO : 0; 338 } 339 340 static int ps8622_backlight_update(struct backlight_device *bl) 341 { 342 struct ps8622_bridge *ps8622 = dev_get_drvdata(&bl->dev); 343 int ret, brightness = bl->props.brightness; 344 345 if (bl->props.power != FB_BLANK_UNBLANK || 346 bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) 347 brightness = 0; 348 349 if (!ps8622->enabled) 350 return -EINVAL; 351 352 ret = ps8622_set(ps8622->client, 0x01, 0xa7, brightness); 353 354 return ret; 355 } 356 357 static const struct backlight_ops ps8622_backlight_ops = { 358 .update_status = ps8622_backlight_update, 359 }; 360 361 static void ps8622_pre_enable(struct drm_bridge *bridge) 362 { 363 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 364 int ret; 365 366 if (ps8622->enabled) 367 return; 368 369 gpiod_set_value(ps8622->gpio_rst, 0); 370 371 if (ps8622->v12) { 372 ret = regulator_enable(ps8622->v12); 373 if (ret) 374 DRM_ERROR("fails to enable ps8622->v12"); 375 } 376 377 if (drm_panel_prepare(ps8622->panel)) { 378 DRM_ERROR("failed to prepare panel\n"); 379 return; 380 } 381 382 gpiod_set_value(ps8622->gpio_slp, 1); 383 384 /* 385 * T1 is the range of time that it takes for the power to rise after we 386 * enable the lcd/ps8622 fet. T2 is the range of time in which the 387 * data sheet specifies we should deassert the reset pin. 388 * 389 * If it takes T1.max for the power to rise, we need to wait atleast 390 * T2.min before deasserting the reset pin. If it takes T1.min for the 391 * power to rise, we need to wait at most T2.max before deasserting the 392 * reset pin. 393 */ 394 usleep_range(PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US, 395 PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US); 396 397 gpiod_set_value(ps8622->gpio_rst, 1); 398 399 /* wait 20ms after RST high */ 400 usleep_range(20000, 30000); 401 402 ret = ps8622_send_config(ps8622); 403 if (ret) { 404 DRM_ERROR("Failed to send config to bridge (%d)\n", ret); 405 return; 406 } 407 408 ps8622->enabled = true; 409 } 410 411 static void ps8622_enable(struct drm_bridge *bridge) 412 { 413 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 414 415 if (drm_panel_enable(ps8622->panel)) { 416 DRM_ERROR("failed to enable panel\n"); 417 return; 418 } 419 } 420 421 static void ps8622_disable(struct drm_bridge *bridge) 422 { 423 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 424 425 if (drm_panel_disable(ps8622->panel)) { 426 DRM_ERROR("failed to disable panel\n"); 427 return; 428 } 429 msleep(PS8622_PWMO_END_T12_MS); 430 } 431 432 static void ps8622_post_disable(struct drm_bridge *bridge) 433 { 434 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 435 436 if (!ps8622->enabled) 437 return; 438 439 ps8622->enabled = false; 440 441 /* 442 * This doesn't matter if the regulators are turned off, but something 443 * else might keep them on. In that case, we want to assert the slp gpio 444 * to lower power. 445 */ 446 gpiod_set_value(ps8622->gpio_slp, 0); 447 448 if (drm_panel_unprepare(ps8622->panel)) { 449 DRM_ERROR("failed to unprepare panel\n"); 450 return; 451 } 452 453 if (ps8622->v12) 454 regulator_disable(ps8622->v12); 455 456 /* 457 * Sleep for at least the amount of time that it takes the power rail to 458 * fall to prevent asserting the rst gpio from doing anything. 459 */ 460 usleep_range(PS8622_POWER_FALL_T16_MAX_US, 461 2 * PS8622_POWER_FALL_T16_MAX_US); 462 gpiod_set_value(ps8622->gpio_rst, 0); 463 464 msleep(PS8622_POWER_OFF_T17_MS); 465 } 466 467 static int ps8622_get_modes(struct drm_connector *connector) 468 { 469 struct ps8622_bridge *ps8622; 470 471 ps8622 = connector_to_ps8622(connector); 472 473 return drm_panel_get_modes(ps8622->panel); 474 } 475 476 static const struct drm_connector_helper_funcs ps8622_connector_helper_funcs = { 477 .get_modes = ps8622_get_modes, 478 }; 479 480 static const struct drm_connector_funcs ps8622_connector_funcs = { 481 .dpms = drm_atomic_helper_connector_dpms, 482 .fill_modes = drm_helper_probe_single_connector_modes, 483 .destroy = drm_connector_cleanup, 484 .reset = drm_atomic_helper_connector_reset, 485 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 486 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 487 }; 488 489 static int ps8622_attach(struct drm_bridge *bridge) 490 { 491 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 492 int ret; 493 494 if (!bridge->encoder) { 495 DRM_ERROR("Parent encoder object not found"); 496 return -ENODEV; 497 } 498 499 ps8622->connector.polled = DRM_CONNECTOR_POLL_HPD; 500 ret = drm_connector_init(bridge->dev, &ps8622->connector, 501 &ps8622_connector_funcs, DRM_MODE_CONNECTOR_LVDS); 502 if (ret) { 503 DRM_ERROR("Failed to initialize connector with drm\n"); 504 return ret; 505 } 506 drm_connector_helper_add(&ps8622->connector, 507 &ps8622_connector_helper_funcs); 508 drm_connector_register(&ps8622->connector); 509 drm_mode_connector_attach_encoder(&ps8622->connector, 510 bridge->encoder); 511 512 if (ps8622->panel) 513 drm_panel_attach(ps8622->panel, &ps8622->connector); 514 515 drm_helper_hpd_irq_event(ps8622->connector.dev); 516 517 return ret; 518 } 519 520 static const struct drm_bridge_funcs ps8622_bridge_funcs = { 521 .pre_enable = ps8622_pre_enable, 522 .enable = ps8622_enable, 523 .disable = ps8622_disable, 524 .post_disable = ps8622_post_disable, 525 .attach = ps8622_attach, 526 }; 527 528 static const struct of_device_id ps8622_devices[] = { 529 {.compatible = "parade,ps8622",}, 530 {.compatible = "parade,ps8625",}, 531 {} 532 }; 533 MODULE_DEVICE_TABLE(of, ps8622_devices); 534 535 static int ps8622_probe(struct i2c_client *client, 536 const struct i2c_device_id *id) 537 { 538 struct device *dev = &client->dev; 539 struct device_node *endpoint, *panel_node; 540 struct ps8622_bridge *ps8622; 541 int ret; 542 543 ps8622 = devm_kzalloc(dev, sizeof(*ps8622), GFP_KERNEL); 544 if (!ps8622) 545 return -ENOMEM; 546 547 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 548 if (endpoint) { 549 panel_node = of_graph_get_remote_port_parent(endpoint); 550 if (panel_node) { 551 ps8622->panel = of_drm_find_panel(panel_node); 552 of_node_put(panel_node); 553 if (!ps8622->panel) 554 return -EPROBE_DEFER; 555 } 556 } 557 558 ps8622->client = client; 559 560 ps8622->v12 = devm_regulator_get(dev, "vdd12"); 561 if (IS_ERR(ps8622->v12)) { 562 dev_info(dev, "no 1.2v regulator found for PS8622\n"); 563 ps8622->v12 = NULL; 564 } 565 566 ps8622->gpio_slp = devm_gpiod_get(dev, "sleep", GPIOD_OUT_HIGH); 567 if (IS_ERR(ps8622->gpio_slp)) { 568 ret = PTR_ERR(ps8622->gpio_slp); 569 dev_err(dev, "cannot get gpio_slp %d\n", ret); 570 return ret; 571 } 572 573 /* 574 * Assert the reset pin high to avoid the bridge being 575 * initialized prematurely 576 */ 577 ps8622->gpio_rst = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 578 if (IS_ERR(ps8622->gpio_rst)) { 579 ret = PTR_ERR(ps8622->gpio_rst); 580 dev_err(dev, "cannot get gpio_rst %d\n", ret); 581 return ret; 582 } 583 584 ps8622->max_lane_count = id->driver_data; 585 586 if (of_property_read_u32(dev->of_node, "lane-count", 587 &ps8622->lane_count)) { 588 ps8622->lane_count = ps8622->max_lane_count; 589 } else if (ps8622->lane_count > ps8622->max_lane_count) { 590 dev_info(dev, "lane-count property is too high," 591 "using max_lane_count\n"); 592 ps8622->lane_count = ps8622->max_lane_count; 593 } 594 595 if (!of_find_property(dev->of_node, "use-external-pwm", NULL)) { 596 ps8622->bl = backlight_device_register("ps8622-backlight", 597 dev, ps8622, &ps8622_backlight_ops, 598 NULL); 599 if (IS_ERR(ps8622->bl)) { 600 DRM_ERROR("failed to register backlight\n"); 601 ret = PTR_ERR(ps8622->bl); 602 ps8622->bl = NULL; 603 return ret; 604 } 605 ps8622->bl->props.max_brightness = PS8622_MAX_BRIGHTNESS; 606 ps8622->bl->props.brightness = PS8622_MAX_BRIGHTNESS; 607 } 608 609 ps8622->bridge.funcs = &ps8622_bridge_funcs; 610 ps8622->bridge.of_node = dev->of_node; 611 ret = drm_bridge_add(&ps8622->bridge); 612 if (ret) { 613 DRM_ERROR("Failed to add bridge\n"); 614 return ret; 615 } 616 617 i2c_set_clientdata(client, ps8622); 618 619 return 0; 620 } 621 622 static int ps8622_remove(struct i2c_client *client) 623 { 624 struct ps8622_bridge *ps8622 = i2c_get_clientdata(client); 625 626 backlight_device_unregister(ps8622->bl); 627 drm_bridge_remove(&ps8622->bridge); 628 629 return 0; 630 } 631 632 static const struct i2c_device_id ps8622_i2c_table[] = { 633 /* Device type, max_lane_count */ 634 {"ps8622", 1}, 635 {"ps8625", 2}, 636 {}, 637 }; 638 MODULE_DEVICE_TABLE(i2c, ps8622_i2c_table); 639 640 static struct i2c_driver ps8622_driver = { 641 .id_table = ps8622_i2c_table, 642 .probe = ps8622_probe, 643 .remove = ps8622_remove, 644 .driver = { 645 .name = "ps8622", 646 .of_match_table = ps8622_devices, 647 }, 648 }; 649 module_i2c_driver(ps8622_driver); 650 651 MODULE_AUTHOR("Vincent Palatin <vpalatin@chromium.org>"); 652 MODULE_DESCRIPTION("Parade ps8622/ps8625 eDP-LVDS converter driver"); 653 MODULE_LICENSE("GPL v2"); 654